1 // SPDX-License-Identifier: GPL-2.0+ 2 /* MDIO Bus interface 3 * 4 * Author: Andy Fleming 5 * 6 * Copyright (c) 2004 Freescale Semiconductor, Inc. 7 */ 8 9 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 10 11 #include <linux/delay.h> 12 #include <linux/device.h> 13 #include <linux/errno.h> 14 #include <linux/etherdevice.h> 15 #include <linux/ethtool.h> 16 #include <linux/gpio.h> 17 #include <linux/gpio/consumer.h> 18 #include <linux/init.h> 19 #include <linux/interrupt.h> 20 #include <linux/io.h> 21 #include <linux/kernel.h> 22 #include <linux/mii.h> 23 #include <linux/mm.h> 24 #include <linux/module.h> 25 #include <linux/netdevice.h> 26 #include <linux/of_device.h> 27 #include <linux/of_gpio.h> 28 #include <linux/of_mdio.h> 29 #include <linux/phy.h> 30 #include <linux/reset.h> 31 #include <linux/skbuff.h> 32 #include <linux/slab.h> 33 #include <linux/spinlock.h> 34 #include <linux/string.h> 35 #include <linux/uaccess.h> 36 #include <linux/unistd.h> 37 38 #define CREATE_TRACE_POINTS 39 #include <trace/events/mdio.h> 40 41 #include "mdio-boardinfo.h" 42 43 static int mdiobus_register_gpiod(struct mdio_device *mdiodev) 44 { 45 /* Deassert the optional reset signal */ 46 mdiodev->reset_gpio = gpiod_get_optional(&mdiodev->dev, 47 "reset", GPIOD_OUT_LOW); 48 if (IS_ERR(mdiodev->reset_gpio)) 49 return PTR_ERR(mdiodev->reset_gpio); 50 51 if (mdiodev->reset_gpio) 52 gpiod_set_consumer_name(mdiodev->reset_gpio, "PHY reset"); 53 54 return 0; 55 } 56 57 static int mdiobus_register_reset(struct mdio_device *mdiodev) 58 { 59 struct reset_control *reset; 60 61 reset = reset_control_get_optional_exclusive(&mdiodev->dev, "phy"); 62 if (IS_ERR(reset)) 63 return PTR_ERR(reset); 64 65 mdiodev->reset_ctrl = reset; 66 67 return 0; 68 } 69 70 int mdiobus_register_device(struct mdio_device *mdiodev) 71 { 72 int err; 73 74 if (mdiodev->bus->mdio_map[mdiodev->addr]) 75 return -EBUSY; 76 77 if (mdiodev->flags & MDIO_DEVICE_FLAG_PHY) { 78 err = mdiobus_register_gpiod(mdiodev); 79 if (err) 80 return err; 81 82 err = mdiobus_register_reset(mdiodev); 83 if (err) 84 return err; 85 86 /* Assert the reset signal */ 87 mdio_device_reset(mdiodev, 1); 88 } 89 90 mdiodev->bus->mdio_map[mdiodev->addr] = mdiodev; 91 92 return 0; 93 } 94 EXPORT_SYMBOL(mdiobus_register_device); 95 96 int mdiobus_unregister_device(struct mdio_device *mdiodev) 97 { 98 if (mdiodev->bus->mdio_map[mdiodev->addr] != mdiodev) 99 return -EINVAL; 100 101 reset_control_put(mdiodev->reset_ctrl); 102 103 mdiodev->bus->mdio_map[mdiodev->addr] = NULL; 104 105 return 0; 106 } 107 EXPORT_SYMBOL(mdiobus_unregister_device); 108 109 struct phy_device *mdiobus_get_phy(struct mii_bus *bus, int addr) 110 { 111 struct mdio_device *mdiodev = bus->mdio_map[addr]; 112 113 if (!mdiodev) 114 return NULL; 115 116 if (!(mdiodev->flags & MDIO_DEVICE_FLAG_PHY)) 117 return NULL; 118 119 return container_of(mdiodev, struct phy_device, mdio); 120 } 121 EXPORT_SYMBOL(mdiobus_get_phy); 122 123 bool mdiobus_is_registered_device(struct mii_bus *bus, int addr) 124 { 125 return bus->mdio_map[addr]; 126 } 127 EXPORT_SYMBOL(mdiobus_is_registered_device); 128 129 /** 130 * mdiobus_alloc_size - allocate a mii_bus structure 131 * @size: extra amount of memory to allocate for private storage. 132 * If non-zero, then bus->priv is points to that memory. 133 * 134 * Description: called by a bus driver to allocate an mii_bus 135 * structure to fill in. 136 */ 137 struct mii_bus *mdiobus_alloc_size(size_t size) 138 { 139 struct mii_bus *bus; 140 size_t aligned_size = ALIGN(sizeof(*bus), NETDEV_ALIGN); 141 size_t alloc_size; 142 int i; 143 144 /* If we alloc extra space, it should be aligned */ 145 if (size) 146 alloc_size = aligned_size + size; 147 else 148 alloc_size = sizeof(*bus); 149 150 bus = kzalloc(alloc_size, GFP_KERNEL); 151 if (!bus) 152 return NULL; 153 154 bus->state = MDIOBUS_ALLOCATED; 155 if (size) 156 bus->priv = (void *)bus + aligned_size; 157 158 /* Initialise the interrupts to polling and 64-bit seqcounts */ 159 for (i = 0; i < PHY_MAX_ADDR; i++) { 160 bus->irq[i] = PHY_POLL; 161 u64_stats_init(&bus->stats[i].syncp); 162 } 163 164 return bus; 165 } 166 EXPORT_SYMBOL(mdiobus_alloc_size); 167 168 /** 169 * mdiobus_release - mii_bus device release callback 170 * @d: the target struct device that contains the mii_bus 171 * 172 * Description: called when the last reference to an mii_bus is 173 * dropped, to free the underlying memory. 174 */ 175 static void mdiobus_release(struct device *d) 176 { 177 struct mii_bus *bus = to_mii_bus(d); 178 179 WARN(bus->state != MDIOBUS_RELEASED && 180 /* for compatibility with error handling in drivers */ 181 bus->state != MDIOBUS_ALLOCATED, 182 "%s: not in RELEASED or ALLOCATED state\n", 183 bus->id); 184 kfree(bus); 185 } 186 187 struct mdio_bus_stat_attr { 188 int addr; 189 unsigned int field_offset; 190 }; 191 192 static u64 mdio_bus_get_stat(struct mdio_bus_stats *s, unsigned int offset) 193 { 194 const char *p = (const char *)s + offset; 195 unsigned int start; 196 u64 val = 0; 197 198 do { 199 start = u64_stats_fetch_begin(&s->syncp); 200 val = u64_stats_read((const u64_stats_t *)p); 201 } while (u64_stats_fetch_retry(&s->syncp, start)); 202 203 return val; 204 } 205 206 static u64 mdio_bus_get_global_stat(struct mii_bus *bus, unsigned int offset) 207 { 208 unsigned int i; 209 u64 val = 0; 210 211 for (i = 0; i < PHY_MAX_ADDR; i++) 212 val += mdio_bus_get_stat(&bus->stats[i], offset); 213 214 return val; 215 } 216 217 static ssize_t mdio_bus_stat_field_show(struct device *dev, 218 struct device_attribute *attr, 219 char *buf) 220 { 221 struct mii_bus *bus = to_mii_bus(dev); 222 struct mdio_bus_stat_attr *sattr; 223 struct dev_ext_attribute *eattr; 224 u64 val; 225 226 eattr = container_of(attr, struct dev_ext_attribute, attr); 227 sattr = eattr->var; 228 229 if (sattr->addr < 0) 230 val = mdio_bus_get_global_stat(bus, sattr->field_offset); 231 else 232 val = mdio_bus_get_stat(&bus->stats[sattr->addr], 233 sattr->field_offset); 234 235 return sprintf(buf, "%llu\n", val); 236 } 237 238 static ssize_t mdio_bus_device_stat_field_show(struct device *dev, 239 struct device_attribute *attr, 240 char *buf) 241 { 242 struct mdio_device *mdiodev = to_mdio_device(dev); 243 struct mii_bus *bus = mdiodev->bus; 244 struct mdio_bus_stat_attr *sattr; 245 struct dev_ext_attribute *eattr; 246 int addr = mdiodev->addr; 247 u64 val; 248 249 eattr = container_of(attr, struct dev_ext_attribute, attr); 250 sattr = eattr->var; 251 252 val = mdio_bus_get_stat(&bus->stats[addr], sattr->field_offset); 253 254 return sprintf(buf, "%llu\n", val); 255 } 256 257 #define MDIO_BUS_STATS_ATTR_DECL(field, file) \ 258 static struct dev_ext_attribute dev_attr_mdio_bus_##field = { \ 259 .attr = { .attr = { .name = file, .mode = 0444 }, \ 260 .show = mdio_bus_stat_field_show, \ 261 }, \ 262 .var = &((struct mdio_bus_stat_attr) { \ 263 -1, offsetof(struct mdio_bus_stats, field) \ 264 }), \ 265 }; \ 266 static struct dev_ext_attribute dev_attr_mdio_bus_device_##field = { \ 267 .attr = { .attr = { .name = file, .mode = 0444 }, \ 268 .show = mdio_bus_device_stat_field_show, \ 269 }, \ 270 .var = &((struct mdio_bus_stat_attr) { \ 271 -1, offsetof(struct mdio_bus_stats, field) \ 272 }), \ 273 }; 274 275 #define MDIO_BUS_STATS_ATTR(field) \ 276 MDIO_BUS_STATS_ATTR_DECL(field, __stringify(field)) 277 278 MDIO_BUS_STATS_ATTR(transfers); 279 MDIO_BUS_STATS_ATTR(errors); 280 MDIO_BUS_STATS_ATTR(writes); 281 MDIO_BUS_STATS_ATTR(reads); 282 283 #define MDIO_BUS_STATS_ADDR_ATTR_DECL(field, addr, file) \ 284 static struct dev_ext_attribute dev_attr_mdio_bus_addr_##field##_##addr = { \ 285 .attr = { .attr = { .name = file, .mode = 0444 }, \ 286 .show = mdio_bus_stat_field_show, \ 287 }, \ 288 .var = &((struct mdio_bus_stat_attr) { \ 289 addr, offsetof(struct mdio_bus_stats, field) \ 290 }), \ 291 } 292 293 #define MDIO_BUS_STATS_ADDR_ATTR(field, addr) \ 294 MDIO_BUS_STATS_ADDR_ATTR_DECL(field, addr, \ 295 __stringify(field) "_" __stringify(addr)) 296 297 #define MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(addr) \ 298 MDIO_BUS_STATS_ADDR_ATTR(transfers, addr); \ 299 MDIO_BUS_STATS_ADDR_ATTR(errors, addr); \ 300 MDIO_BUS_STATS_ADDR_ATTR(writes, addr); \ 301 MDIO_BUS_STATS_ADDR_ATTR(reads, addr) \ 302 303 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(0); 304 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(1); 305 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(2); 306 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(3); 307 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(4); 308 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(5); 309 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(6); 310 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(7); 311 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(8); 312 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(9); 313 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(10); 314 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(11); 315 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(12); 316 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(13); 317 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(14); 318 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(15); 319 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(16); 320 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(17); 321 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(18); 322 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(19); 323 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(20); 324 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(21); 325 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(22); 326 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(23); 327 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(24); 328 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(25); 329 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(26); 330 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(27); 331 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(28); 332 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(29); 333 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(30); 334 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(31); 335 336 #define MDIO_BUS_STATS_ADDR_ATTR_GROUP(addr) \ 337 &dev_attr_mdio_bus_addr_transfers_##addr.attr.attr, \ 338 &dev_attr_mdio_bus_addr_errors_##addr.attr.attr, \ 339 &dev_attr_mdio_bus_addr_writes_##addr.attr.attr, \ 340 &dev_attr_mdio_bus_addr_reads_##addr.attr.attr \ 341 342 static struct attribute *mdio_bus_statistics_attrs[] = { 343 &dev_attr_mdio_bus_transfers.attr.attr, 344 &dev_attr_mdio_bus_errors.attr.attr, 345 &dev_attr_mdio_bus_writes.attr.attr, 346 &dev_attr_mdio_bus_reads.attr.attr, 347 MDIO_BUS_STATS_ADDR_ATTR_GROUP(0), 348 MDIO_BUS_STATS_ADDR_ATTR_GROUP(1), 349 MDIO_BUS_STATS_ADDR_ATTR_GROUP(2), 350 MDIO_BUS_STATS_ADDR_ATTR_GROUP(3), 351 MDIO_BUS_STATS_ADDR_ATTR_GROUP(4), 352 MDIO_BUS_STATS_ADDR_ATTR_GROUP(5), 353 MDIO_BUS_STATS_ADDR_ATTR_GROUP(6), 354 MDIO_BUS_STATS_ADDR_ATTR_GROUP(7), 355 MDIO_BUS_STATS_ADDR_ATTR_GROUP(8), 356 MDIO_BUS_STATS_ADDR_ATTR_GROUP(9), 357 MDIO_BUS_STATS_ADDR_ATTR_GROUP(10), 358 MDIO_BUS_STATS_ADDR_ATTR_GROUP(11), 359 MDIO_BUS_STATS_ADDR_ATTR_GROUP(12), 360 MDIO_BUS_STATS_ADDR_ATTR_GROUP(13), 361 MDIO_BUS_STATS_ADDR_ATTR_GROUP(14), 362 MDIO_BUS_STATS_ADDR_ATTR_GROUP(15), 363 MDIO_BUS_STATS_ADDR_ATTR_GROUP(16), 364 MDIO_BUS_STATS_ADDR_ATTR_GROUP(17), 365 MDIO_BUS_STATS_ADDR_ATTR_GROUP(18), 366 MDIO_BUS_STATS_ADDR_ATTR_GROUP(19), 367 MDIO_BUS_STATS_ADDR_ATTR_GROUP(20), 368 MDIO_BUS_STATS_ADDR_ATTR_GROUP(21), 369 MDIO_BUS_STATS_ADDR_ATTR_GROUP(22), 370 MDIO_BUS_STATS_ADDR_ATTR_GROUP(23), 371 MDIO_BUS_STATS_ADDR_ATTR_GROUP(24), 372 MDIO_BUS_STATS_ADDR_ATTR_GROUP(25), 373 MDIO_BUS_STATS_ADDR_ATTR_GROUP(26), 374 MDIO_BUS_STATS_ADDR_ATTR_GROUP(27), 375 MDIO_BUS_STATS_ADDR_ATTR_GROUP(28), 376 MDIO_BUS_STATS_ADDR_ATTR_GROUP(29), 377 MDIO_BUS_STATS_ADDR_ATTR_GROUP(30), 378 MDIO_BUS_STATS_ADDR_ATTR_GROUP(31), 379 NULL, 380 }; 381 382 static const struct attribute_group mdio_bus_statistics_group = { 383 .name = "statistics", 384 .attrs = mdio_bus_statistics_attrs, 385 }; 386 387 static const struct attribute_group *mdio_bus_groups[] = { 388 &mdio_bus_statistics_group, 389 NULL, 390 }; 391 392 static struct class mdio_bus_class = { 393 .name = "mdio_bus", 394 .dev_release = mdiobus_release, 395 .dev_groups = mdio_bus_groups, 396 }; 397 398 /** 399 * mdio_find_bus - Given the name of a mdiobus, find the mii_bus. 400 * @mdio_name: The name of a mdiobus. 401 * 402 * Returns a reference to the mii_bus, or NULL if none found. The 403 * embedded struct device will have its reference count incremented, 404 * and this must be put_deviced'ed once the bus is finished with. 405 */ 406 struct mii_bus *mdio_find_bus(const char *mdio_name) 407 { 408 struct device *d; 409 410 d = class_find_device_by_name(&mdio_bus_class, mdio_name); 411 return d ? to_mii_bus(d) : NULL; 412 } 413 EXPORT_SYMBOL(mdio_find_bus); 414 415 #if IS_ENABLED(CONFIG_OF_MDIO) 416 /** 417 * of_mdio_find_bus - Given an mii_bus node, find the mii_bus. 418 * @mdio_bus_np: Pointer to the mii_bus. 419 * 420 * Returns a reference to the mii_bus, or NULL if none found. The 421 * embedded struct device will have its reference count incremented, 422 * and this must be put once the bus is finished with. 423 * 424 * Because the association of a device_node and mii_bus is made via 425 * of_mdiobus_register(), the mii_bus cannot be found before it is 426 * registered with of_mdiobus_register(). 427 * 428 */ 429 struct mii_bus *of_mdio_find_bus(struct device_node *mdio_bus_np) 430 { 431 struct device *d; 432 433 if (!mdio_bus_np) 434 return NULL; 435 436 d = class_find_device_by_of_node(&mdio_bus_class, mdio_bus_np); 437 return d ? to_mii_bus(d) : NULL; 438 } 439 EXPORT_SYMBOL(of_mdio_find_bus); 440 441 /* Walk the list of subnodes of a mdio bus and look for a node that 442 * matches the mdio device's address with its 'reg' property. If 443 * found, set the of_node pointer for the mdio device. This allows 444 * auto-probed phy devices to be supplied with information passed in 445 * via DT. 446 */ 447 static void of_mdiobus_link_mdiodev(struct mii_bus *bus, 448 struct mdio_device *mdiodev) 449 { 450 struct device *dev = &mdiodev->dev; 451 struct device_node *child; 452 453 if (dev->of_node || !bus->dev.of_node) 454 return; 455 456 for_each_available_child_of_node(bus->dev.of_node, child) { 457 int addr; 458 459 addr = of_mdio_parse_addr(dev, child); 460 if (addr < 0) 461 continue; 462 463 if (addr == mdiodev->addr) { 464 device_set_node(dev, of_fwnode_handle(child)); 465 /* The refcount on "child" is passed to the mdio 466 * device. Do _not_ use of_node_put(child) here. 467 */ 468 return; 469 } 470 } 471 } 472 #else /* !IS_ENABLED(CONFIG_OF_MDIO) */ 473 static inline void of_mdiobus_link_mdiodev(struct mii_bus *mdio, 474 struct mdio_device *mdiodev) 475 { 476 } 477 #endif 478 479 /** 480 * mdiobus_create_device - create a full MDIO device given 481 * a mdio_board_info structure 482 * @bus: MDIO bus to create the devices on 483 * @bi: mdio_board_info structure describing the devices 484 * 485 * Returns 0 on success or < 0 on error. 486 */ 487 static int mdiobus_create_device(struct mii_bus *bus, 488 struct mdio_board_info *bi) 489 { 490 struct mdio_device *mdiodev; 491 int ret = 0; 492 493 mdiodev = mdio_device_create(bus, bi->mdio_addr); 494 if (IS_ERR(mdiodev)) 495 return -ENODEV; 496 497 strncpy(mdiodev->modalias, bi->modalias, 498 sizeof(mdiodev->modalias)); 499 mdiodev->bus_match = mdio_device_bus_match; 500 mdiodev->dev.platform_data = (void *)bi->platform_data; 501 502 ret = mdio_device_register(mdiodev); 503 if (ret) 504 mdio_device_free(mdiodev); 505 506 return ret; 507 } 508 509 /** 510 * __mdiobus_register - bring up all the PHYs on a given bus and attach them to bus 511 * @bus: target mii_bus 512 * @owner: module containing bus accessor functions 513 * 514 * Description: Called by a bus driver to bring up all the PHYs 515 * on a given bus, and attach them to the bus. Drivers should use 516 * mdiobus_register() rather than __mdiobus_register() unless they 517 * need to pass a specific owner module. MDIO devices which are not 518 * PHYs will not be brought up by this function. They are expected 519 * to be explicitly listed in DT and instantiated by of_mdiobus_register(). 520 * 521 * Returns 0 on success or < 0 on error. 522 */ 523 int __mdiobus_register(struct mii_bus *bus, struct module *owner) 524 { 525 struct mdio_device *mdiodev; 526 int i, err; 527 struct gpio_desc *gpiod; 528 529 if (NULL == bus || NULL == bus->name || 530 NULL == bus->read || NULL == bus->write) 531 return -EINVAL; 532 533 if (bus->parent && bus->parent->of_node) 534 bus->parent->of_node->fwnode.flags |= 535 FWNODE_FLAG_NEEDS_CHILD_BOUND_ON_ADD; 536 537 WARN(bus->state != MDIOBUS_ALLOCATED && 538 bus->state != MDIOBUS_UNREGISTERED, 539 "%s: not in ALLOCATED or UNREGISTERED state\n", bus->id); 540 541 bus->owner = owner; 542 bus->dev.parent = bus->parent; 543 bus->dev.class = &mdio_bus_class; 544 bus->dev.groups = NULL; 545 dev_set_name(&bus->dev, "%s", bus->id); 546 547 /* We need to set state to MDIOBUS_UNREGISTERED to correctly release 548 * the device in mdiobus_free() 549 * 550 * State will be updated later in this function in case of success 551 */ 552 bus->state = MDIOBUS_UNREGISTERED; 553 554 err = device_register(&bus->dev); 555 if (err) { 556 pr_err("mii_bus %s failed to register\n", bus->id); 557 return -EINVAL; 558 } 559 560 mutex_init(&bus->mdio_lock); 561 mutex_init(&bus->shared_lock); 562 563 /* assert bus level PHY GPIO reset */ 564 gpiod = devm_gpiod_get_optional(&bus->dev, "reset", GPIOD_OUT_HIGH); 565 if (IS_ERR(gpiod)) { 566 err = dev_err_probe(&bus->dev, PTR_ERR(gpiod), 567 "mii_bus %s couldn't get reset GPIO\n", 568 bus->id); 569 device_del(&bus->dev); 570 return err; 571 } else if (gpiod) { 572 bus->reset_gpiod = gpiod; 573 fsleep(bus->reset_delay_us); 574 gpiod_set_value_cansleep(gpiod, 0); 575 if (bus->reset_post_delay_us > 0) 576 fsleep(bus->reset_post_delay_us); 577 } 578 579 if (bus->reset) { 580 err = bus->reset(bus); 581 if (err) 582 goto error_reset_gpiod; 583 } 584 585 for (i = 0; i < PHY_MAX_ADDR; i++) { 586 if ((bus->phy_mask & (1 << i)) == 0) { 587 struct phy_device *phydev; 588 589 phydev = mdiobus_scan(bus, i); 590 if (IS_ERR(phydev) && (PTR_ERR(phydev) != -ENODEV)) { 591 err = PTR_ERR(phydev); 592 goto error; 593 } 594 } 595 } 596 597 mdiobus_setup_mdiodev_from_board_info(bus, mdiobus_create_device); 598 599 bus->state = MDIOBUS_REGISTERED; 600 dev_dbg(&bus->dev, "probed\n"); 601 return 0; 602 603 error: 604 while (--i >= 0) { 605 mdiodev = bus->mdio_map[i]; 606 if (!mdiodev) 607 continue; 608 609 mdiodev->device_remove(mdiodev); 610 mdiodev->device_free(mdiodev); 611 } 612 error_reset_gpiod: 613 /* Put PHYs in RESET to save power */ 614 if (bus->reset_gpiod) 615 gpiod_set_value_cansleep(bus->reset_gpiod, 1); 616 617 device_del(&bus->dev); 618 return err; 619 } 620 EXPORT_SYMBOL(__mdiobus_register); 621 622 void mdiobus_unregister(struct mii_bus *bus) 623 { 624 struct mdio_device *mdiodev; 625 int i; 626 627 if (WARN_ON_ONCE(bus->state != MDIOBUS_REGISTERED)) 628 return; 629 bus->state = MDIOBUS_UNREGISTERED; 630 631 for (i = 0; i < PHY_MAX_ADDR; i++) { 632 mdiodev = bus->mdio_map[i]; 633 if (!mdiodev) 634 continue; 635 636 if (mdiodev->reset_gpio) 637 gpiod_put(mdiodev->reset_gpio); 638 639 mdiodev->device_remove(mdiodev); 640 mdiodev->device_free(mdiodev); 641 } 642 643 /* Put PHYs in RESET to save power */ 644 if (bus->reset_gpiod) 645 gpiod_set_value_cansleep(bus->reset_gpiod, 1); 646 647 device_del(&bus->dev); 648 } 649 EXPORT_SYMBOL(mdiobus_unregister); 650 651 /** 652 * mdiobus_free - free a struct mii_bus 653 * @bus: mii_bus to free 654 * 655 * This function releases the reference to the underlying device 656 * object in the mii_bus. If this is the last reference, the mii_bus 657 * will be freed. 658 */ 659 void mdiobus_free(struct mii_bus *bus) 660 { 661 /* For compatibility with error handling in drivers. */ 662 if (bus->state == MDIOBUS_ALLOCATED) { 663 kfree(bus); 664 return; 665 } 666 667 WARN(bus->state != MDIOBUS_UNREGISTERED, 668 "%s: not in UNREGISTERED state\n", bus->id); 669 bus->state = MDIOBUS_RELEASED; 670 671 put_device(&bus->dev); 672 } 673 EXPORT_SYMBOL(mdiobus_free); 674 675 /** 676 * mdiobus_scan - scan a bus for MDIO devices. 677 * @bus: mii_bus to scan 678 * @addr: address on bus to scan 679 * 680 * This function scans the MDIO bus, looking for devices which can be 681 * identified using a vendor/product ID in registers 2 and 3. Not all 682 * MDIO devices have such registers, but PHY devices typically 683 * do. Hence this function assumes anything found is a PHY, or can be 684 * treated as a PHY. Other MDIO devices, such as switches, will 685 * probably not be found during the scan. 686 */ 687 struct phy_device *mdiobus_scan(struct mii_bus *bus, int addr) 688 { 689 struct phy_device *phydev = ERR_PTR(-ENODEV); 690 int err; 691 692 switch (bus->probe_capabilities) { 693 case MDIOBUS_NO_CAP: 694 case MDIOBUS_C22: 695 phydev = get_phy_device(bus, addr, false); 696 break; 697 case MDIOBUS_C45: 698 phydev = get_phy_device(bus, addr, true); 699 break; 700 case MDIOBUS_C22_C45: 701 phydev = get_phy_device(bus, addr, false); 702 if (IS_ERR(phydev)) 703 phydev = get_phy_device(bus, addr, true); 704 break; 705 } 706 707 if (IS_ERR(phydev)) 708 return phydev; 709 710 /* 711 * For DT, see if the auto-probed phy has a correspoding child 712 * in the bus node, and set the of_node pointer in this case. 713 */ 714 of_mdiobus_link_mdiodev(bus, &phydev->mdio); 715 716 err = phy_device_register(phydev); 717 if (err) { 718 phy_device_free(phydev); 719 return ERR_PTR(-ENODEV); 720 } 721 722 return phydev; 723 } 724 EXPORT_SYMBOL(mdiobus_scan); 725 726 static void mdiobus_stats_acct(struct mdio_bus_stats *stats, bool op, int ret) 727 { 728 preempt_disable(); 729 u64_stats_update_begin(&stats->syncp); 730 731 u64_stats_inc(&stats->transfers); 732 if (ret < 0) { 733 u64_stats_inc(&stats->errors); 734 goto out; 735 } 736 737 if (op) 738 u64_stats_inc(&stats->reads); 739 else 740 u64_stats_inc(&stats->writes); 741 out: 742 u64_stats_update_end(&stats->syncp); 743 preempt_enable(); 744 } 745 746 /** 747 * __mdiobus_read - Unlocked version of the mdiobus_read function 748 * @bus: the mii_bus struct 749 * @addr: the phy address 750 * @regnum: register number to read 751 * 752 * Read a MDIO bus register. Caller must hold the mdio bus lock. 753 * 754 * NOTE: MUST NOT be called from interrupt context. 755 */ 756 int __mdiobus_read(struct mii_bus *bus, int addr, u32 regnum) 757 { 758 int retval; 759 760 lockdep_assert_held_once(&bus->mdio_lock); 761 762 retval = bus->read(bus, addr, regnum); 763 764 trace_mdio_access(bus, 1, addr, regnum, retval, retval); 765 mdiobus_stats_acct(&bus->stats[addr], true, retval); 766 767 return retval; 768 } 769 EXPORT_SYMBOL(__mdiobus_read); 770 771 /** 772 * __mdiobus_write - Unlocked version of the mdiobus_write function 773 * @bus: the mii_bus struct 774 * @addr: the phy address 775 * @regnum: register number to write 776 * @val: value to write to @regnum 777 * 778 * Write a MDIO bus register. Caller must hold the mdio bus lock. 779 * 780 * NOTE: MUST NOT be called from interrupt context. 781 */ 782 int __mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val) 783 { 784 int err; 785 786 lockdep_assert_held_once(&bus->mdio_lock); 787 788 err = bus->write(bus, addr, regnum, val); 789 790 trace_mdio_access(bus, 0, addr, regnum, val, err); 791 mdiobus_stats_acct(&bus->stats[addr], false, err); 792 793 return err; 794 } 795 EXPORT_SYMBOL(__mdiobus_write); 796 797 /** 798 * __mdiobus_modify_changed - Unlocked version of the mdiobus_modify function 799 * @bus: the mii_bus struct 800 * @addr: the phy address 801 * @regnum: register number to modify 802 * @mask: bit mask of bits to clear 803 * @set: bit mask of bits to set 804 * 805 * Read, modify, and if any change, write the register value back to the 806 * device. Any error returns a negative number. 807 * 808 * NOTE: MUST NOT be called from interrupt context. 809 */ 810 int __mdiobus_modify_changed(struct mii_bus *bus, int addr, u32 regnum, 811 u16 mask, u16 set) 812 { 813 int new, ret; 814 815 ret = __mdiobus_read(bus, addr, regnum); 816 if (ret < 0) 817 return ret; 818 819 new = (ret & ~mask) | set; 820 if (new == ret) 821 return 0; 822 823 ret = __mdiobus_write(bus, addr, regnum, new); 824 825 return ret < 0 ? ret : 1; 826 } 827 EXPORT_SYMBOL_GPL(__mdiobus_modify_changed); 828 829 /** 830 * mdiobus_read_nested - Nested version of the mdiobus_read function 831 * @bus: the mii_bus struct 832 * @addr: the phy address 833 * @regnum: register number to read 834 * 835 * In case of nested MDIO bus access avoid lockdep false positives by 836 * using mutex_lock_nested(). 837 * 838 * NOTE: MUST NOT be called from interrupt context, 839 * because the bus read/write functions may wait for an interrupt 840 * to conclude the operation. 841 */ 842 int mdiobus_read_nested(struct mii_bus *bus, int addr, u32 regnum) 843 { 844 int retval; 845 846 mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED); 847 retval = __mdiobus_read(bus, addr, regnum); 848 mutex_unlock(&bus->mdio_lock); 849 850 return retval; 851 } 852 EXPORT_SYMBOL(mdiobus_read_nested); 853 854 /** 855 * mdiobus_read - Convenience function for reading a given MII mgmt register 856 * @bus: the mii_bus struct 857 * @addr: the phy address 858 * @regnum: register number to read 859 * 860 * NOTE: MUST NOT be called from interrupt context, 861 * because the bus read/write functions may wait for an interrupt 862 * to conclude the operation. 863 */ 864 int mdiobus_read(struct mii_bus *bus, int addr, u32 regnum) 865 { 866 int retval; 867 868 mutex_lock(&bus->mdio_lock); 869 retval = __mdiobus_read(bus, addr, regnum); 870 mutex_unlock(&bus->mdio_lock); 871 872 return retval; 873 } 874 EXPORT_SYMBOL(mdiobus_read); 875 876 /** 877 * mdiobus_write_nested - Nested version of the mdiobus_write function 878 * @bus: the mii_bus struct 879 * @addr: the phy address 880 * @regnum: register number to write 881 * @val: value to write to @regnum 882 * 883 * In case of nested MDIO bus access avoid lockdep false positives by 884 * using mutex_lock_nested(). 885 * 886 * NOTE: MUST NOT be called from interrupt context, 887 * because the bus read/write functions may wait for an interrupt 888 * to conclude the operation. 889 */ 890 int mdiobus_write_nested(struct mii_bus *bus, int addr, u32 regnum, u16 val) 891 { 892 int err; 893 894 mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED); 895 err = __mdiobus_write(bus, addr, regnum, val); 896 mutex_unlock(&bus->mdio_lock); 897 898 return err; 899 } 900 EXPORT_SYMBOL(mdiobus_write_nested); 901 902 /** 903 * mdiobus_write - Convenience function for writing a given MII mgmt register 904 * @bus: the mii_bus struct 905 * @addr: the phy address 906 * @regnum: register number to write 907 * @val: value to write to @regnum 908 * 909 * NOTE: MUST NOT be called from interrupt context, 910 * because the bus read/write functions may wait for an interrupt 911 * to conclude the operation. 912 */ 913 int mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val) 914 { 915 int err; 916 917 mutex_lock(&bus->mdio_lock); 918 err = __mdiobus_write(bus, addr, regnum, val); 919 mutex_unlock(&bus->mdio_lock); 920 921 return err; 922 } 923 EXPORT_SYMBOL(mdiobus_write); 924 925 /** 926 * mdiobus_modify - Convenience function for modifying a given mdio device 927 * register 928 * @bus: the mii_bus struct 929 * @addr: the phy address 930 * @regnum: register number to write 931 * @mask: bit mask of bits to clear 932 * @set: bit mask of bits to set 933 */ 934 int mdiobus_modify(struct mii_bus *bus, int addr, u32 regnum, u16 mask, u16 set) 935 { 936 int err; 937 938 mutex_lock(&bus->mdio_lock); 939 err = __mdiobus_modify_changed(bus, addr, regnum, mask, set); 940 mutex_unlock(&bus->mdio_lock); 941 942 return err < 0 ? err : 0; 943 } 944 EXPORT_SYMBOL_GPL(mdiobus_modify); 945 946 /** 947 * mdiobus_modify_changed - Convenience function for modifying a given mdio 948 * device register and returning if it changed 949 * @bus: the mii_bus struct 950 * @addr: the phy address 951 * @regnum: register number to write 952 * @mask: bit mask of bits to clear 953 * @set: bit mask of bits to set 954 */ 955 int mdiobus_modify_changed(struct mii_bus *bus, int addr, u32 regnum, 956 u16 mask, u16 set) 957 { 958 int err; 959 960 mutex_lock(&bus->mdio_lock); 961 err = __mdiobus_modify_changed(bus, addr, regnum, mask, set); 962 mutex_unlock(&bus->mdio_lock); 963 964 return err; 965 } 966 EXPORT_SYMBOL_GPL(mdiobus_modify_changed); 967 968 /** 969 * mdio_bus_match - determine if given MDIO driver supports the given 970 * MDIO device 971 * @dev: target MDIO device 972 * @drv: given MDIO driver 973 * 974 * Description: Given a MDIO device, and a MDIO driver, return 1 if 975 * the driver supports the device. Otherwise, return 0. This may 976 * require calling the devices own match function, since different classes 977 * of MDIO devices have different match criteria. 978 */ 979 static int mdio_bus_match(struct device *dev, struct device_driver *drv) 980 { 981 struct mdio_driver *mdiodrv = to_mdio_driver(drv); 982 struct mdio_device *mdio = to_mdio_device(dev); 983 984 /* Both the driver and device must type-match */ 985 if (!(mdiodrv->mdiodrv.flags & MDIO_DEVICE_IS_PHY) != 986 !(mdio->flags & MDIO_DEVICE_FLAG_PHY)) 987 return 0; 988 989 if (of_driver_match_device(dev, drv)) 990 return 1; 991 992 if (mdio->bus_match) 993 return mdio->bus_match(dev, drv); 994 995 return 0; 996 } 997 998 static int mdio_uevent(struct device *dev, struct kobj_uevent_env *env) 999 { 1000 int rc; 1001 1002 /* Some devices have extra OF data and an OF-style MODALIAS */ 1003 rc = of_device_uevent_modalias(dev, env); 1004 if (rc != -ENODEV) 1005 return rc; 1006 1007 return 0; 1008 } 1009 1010 static struct attribute *mdio_bus_device_statistics_attrs[] = { 1011 &dev_attr_mdio_bus_device_transfers.attr.attr, 1012 &dev_attr_mdio_bus_device_errors.attr.attr, 1013 &dev_attr_mdio_bus_device_writes.attr.attr, 1014 &dev_attr_mdio_bus_device_reads.attr.attr, 1015 NULL, 1016 }; 1017 1018 static const struct attribute_group mdio_bus_device_statistics_group = { 1019 .name = "statistics", 1020 .attrs = mdio_bus_device_statistics_attrs, 1021 }; 1022 1023 static const struct attribute_group *mdio_bus_dev_groups[] = { 1024 &mdio_bus_device_statistics_group, 1025 NULL, 1026 }; 1027 1028 struct bus_type mdio_bus_type = { 1029 .name = "mdio_bus", 1030 .dev_groups = mdio_bus_dev_groups, 1031 .match = mdio_bus_match, 1032 .uevent = mdio_uevent, 1033 }; 1034 EXPORT_SYMBOL(mdio_bus_type); 1035 1036 int __init mdio_bus_init(void) 1037 { 1038 int ret; 1039 1040 ret = class_register(&mdio_bus_class); 1041 if (!ret) { 1042 ret = bus_register(&mdio_bus_type); 1043 if (ret) 1044 class_unregister(&mdio_bus_class); 1045 } 1046 1047 return ret; 1048 } 1049 1050 #if IS_ENABLED(CONFIG_PHYLIB) 1051 void mdio_bus_exit(void) 1052 { 1053 class_unregister(&mdio_bus_class); 1054 bus_unregister(&mdio_bus_type); 1055 } 1056 EXPORT_SYMBOL_GPL(mdio_bus_exit); 1057 #else 1058 module_init(mdio_bus_init); 1059 /* no module_exit, intentional */ 1060 MODULE_LICENSE("GPL"); 1061 MODULE_DESCRIPTION("MDIO bus/device layer"); 1062 #endif 1063